Commit Graph

466 Commits

Author SHA1 Message Date
Li Xinhai
d7482c0da7 Doc: page_migration: fix numbering for non-LRU movable flags
The non-LRU movable flags part is not relevant to above 3 funcitons, so remove
the number 4.

Signed-off-by: Li Xinhai <lixinhai.lxh@gmail.com>

Link: https://lore.kernel.org/r/20210908145215.592325-1-lixinhai.lxh@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-14 14:54:01 -06:00
Linus Torvalds
2d338201d5 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "147 patches, based on 7d2a07b769.

  Subsystems affected by this patch series: mm (memory-hotplug, rmap,
  ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
  alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
  checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
  selftests, ipc, and scripts"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
  scripts: check_extable: fix typo in user error message
  mm/workingset: correct kernel-doc notations
  ipc: replace costly bailout check in sysvipc_find_ipc()
  selftests/memfd: remove unused variable
  Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
  configs: remove the obsolete CONFIG_INPUT_POLLDEV
  prctl: allow to setup brk for et_dyn executables
  pid: cleanup the stale comment mentioning pidmap_init().
  kernel/fork.c: unexport get_{mm,task}_exe_file
  coredump: fix memleak in dump_vma_snapshot()
  fs/coredump.c: log if a core dump is aborted due to changed file permissions
  nilfs2: use refcount_dec_and_lock() to fix potential UAF
  nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
  nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
  nilfs2: fix NULL pointer in nilfs_##name##_attr_release
  nilfs2: fix memory leak in nilfs_sysfs_create_device_group
  trap: cleanup trap_init()
  init: move usermodehelper_enable() to populate_rootfs()
  ...
2021-09-08 12:55:35 -07:00
SeongJae Park
c4ba6014ae Documentation: add documents for DAMON
This commit adds documents for DAMON under
`Documentation/admin-guide/mm/damon/` and `Documentation/vm/damon/`.

Link: https://lkml.kernel.org/r/20210716081449.22187-11-sj38.park@gmail.com
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Reviewed-by: Fernand Sieber <sieberf@amazon.com>
Reviewed-by: Markus Boehme <markubo@amazon.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Amit Shah <amit@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: David Woodhouse <dwmw@amazon.com>
Cc: Fan Du <fan.du@intel.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Leonard Foerster <foersleo@amazon.de>
Cc: Marco Elver <elver@google.com>
Cc: Maximilian Heyne <mheyne@amazon.de>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08 11:50:25 -07:00
Yang Shi
f653312169 doc: hwpoison: correct the support for hugepage
The hwpoison support for huge page, both hugetlb and THP, has been in
kernel for a while, the statement in document is obsolete, correct it.

Link: https://lkml.kernel.org/r/20210819054116.266126-2-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Mackey <tdmackey@twitter.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Linus Torvalds
71bd934101 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "190 patches.

  Subsystems affected by this patch series: mm (hugetlb, userfaultfd,
  vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock,
  migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap,
  zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc,
  core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs,
  signals, exec, kcov, selftests, compress/decompress, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits)
  ipc/util.c: use binary search for max_idx
  ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock
  ipc: use kmalloc for msg_queue and shmid_kernel
  ipc sem: use kvmalloc for sem_undo allocation
  lib/decompressors: remove set but not used variabled 'level'
  selftests/vm/pkeys: exercise x86 XSAVE init state
  selftests/vm/pkeys: refill shadow register after implicit kernel write
  selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
  kcov: add __no_sanitize_coverage to fix noinstr for all architectures
  exec: remove checks in __register_bimfmt()
  x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned
  hfsplus: report create_date to kstat.btime
  hfsplus: remove unnecessary oom message
  nilfs2: remove redundant continue statement in a while-loop
  kprobes: remove duplicated strong free_insn_page in x86 and s390
  init: print out unknown kernel parameters
  checkpatch: do not complain about positive return values starting with EPOLL
  checkpatch: improve the indented label test
  checkpatch: scripts/spdxcheck.py now requires python3
  ...
2021-07-02 12:08:10 -07:00
Alistair Popple
b756a3b5e7 mm: device exclusive memory access
Some devices require exclusive write access to shared virtual memory (SVM)
ranges to perform atomic operations on that memory.  This requires CPU
page tables to be updated to deny access whilst atomic operations are
occurring.

In order to do this introduce a new swap entry type
(SWP_DEVICE_EXCLUSIVE).  When a SVM range needs to be marked for exclusive
access by a device all page table mappings for the particular range are
replaced with device exclusive swap entries.  This causes any CPU access
to the page to result in a fault.

Faults are resovled by replacing the faulting entry with the original
mapping.  This results in MMU notifiers being called which a driver uses
to update access permissions such as revoking atomic access.  After
notifiers have been called the device will no longer have exclusive access
to the region.

Walking of the page tables to find the target pages is handled by
get_user_pages() rather than a direct page table walk.  A direct page
table walk similar to what migrate_vma_collect()/unmap() does could also
have been utilised.  However this resulted in more code similar in
functionality to what get_user_pages() provides as page faulting is
required to make the PTEs present and to break COW.

[dan.carpenter@oracle.com: fix signedness bug in make_device_exclusive_range()]
  Link: https://lkml.kernel.org/r/YNIz5NVnZ5GiZ3u1@mwanda

Link: https://lkml.kernel.org/r/20210616105937.23201-8-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:03 -07:00
Alistair Popple
6b49bf6ddb mm: rename migrate_pgmap_owner
MMU notifier ranges have a migrate_pgmap_owner field which is used by
drivers to store a pointer.  This is subsequently used by the driver
callback to filter MMU_NOTIFY_MIGRATE events.  Other notifier event types
can also benefit from this filtering, so rename the 'migrate_pgmap_owner'
field to 'owner' and create a new notifier initialisation function to
initialise this field.

Link: https://lkml.kernel.org/r/20210616105937.23201-6-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Suggested-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:03 -07:00
Alistair Popple
cd62734ca6 mm/rmap: split try_to_munlock from try_to_unmap
The behaviour of try_to_unmap_one() is difficult to follow because it
performs different operations based on a fairly large set of flags used in
different combinations.

TTU_MUNLOCK is one such flag.  However it is exclusively used by
try_to_munlock() which specifies no other flags.  Therefore rather than
overload try_to_unmap_one() with unrelated behaviour split this out into
it's own function and remove the flag.

Link: https://lkml.kernel.org/r/20210616105937.23201-4-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:03 -07:00
Linus Torvalds
65090f30ab Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "191 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
  slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
  mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
  mm,hwpoison: make get_hwpoison_page() call get_any_page()
  mm,hwpoison: send SIGBUS with error virutal address
  mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
  mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
  mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
  mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
  docs: remove description of DISCONTIGMEM
  arch, mm: remove stale mentions of DISCONIGMEM
  mm: remove CONFIG_DISCONTIGMEM
  m68k: remove support for DISCONTIGMEM
  arc: remove support for DISCONTIGMEM
  arc: update comment about HIGHMEM implementation
  alpha: remove DISCONTIGMEM and NUMA
  mm/page_alloc: move free_the_page
  mm/page_alloc: fix counting of managed_pages
  mm/page_alloc: improve memmap_pages dbg msg
  mm: drop SECTION_SHIFT in code comments
  mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
  mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
  mm/page_alloc: scale the number of pages that are batch freed
  ...
2021-06-29 17:29:11 -07:00
Mike Rapoport
48d9f3355a docs: remove description of DISCONTIGMEM
Remove description of DISCONTIGMEM from the "Memory Models" document and
update VM sysctl description so that it won't mention DISCONIGMEM.

Link: https://lkml.kernel.org/r/20210608091316.3622-8-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:55 -07:00
Linus Torvalds
233a806b00 This was a reasonably active cycle for documentation; this pull includes:
- Some kernel-doc cleanups.  That script is still regex onslaught from
    hell, but it has gotten a little better.
 
  - Improvements to the checkpatch docs, which are also used by the tool
    itself.
 
  - A major update to the pathname lookup documentation.
 
  - Elimination of :doc: markup, since our automarkup magic can create
    references from filenames without all the extra noise.
 
  - The flurry of Chinese translation activity continues.
 
 Plus, of course, the usual collection of updates, typo fixes, and warning
 fixes.
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Merge tag 'docs-5.14' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This was a reasonably active cycle for documentation; this includes:

   - Some kernel-doc cleanups. That script is still regex onslaught from
     hell, but it has gotten a little better.

   - Improvements to the checkpatch docs, which are also used by the
     tool itself.

   - A major update to the pathname lookup documentation.

   - Elimination of :doc: markup, since our automarkup magic can create
     references from filenames without all the extra noise.

   - The flurry of Chinese translation activity continues.

  Plus, of course, the usual collection of updates, typo fixes, and
  warning fixes"

* tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits)
  docs: path-lookup: use bare function() rather than literals
  docs: path-lookup: update symlink description
  docs: path-lookup: update get_link() ->follow_link description
  docs: path-lookup: update WALK_GET, WALK_PUT desc
  docs: path-lookup: no get_link()
  docs: path-lookup: update i_op->put_link and cookie description
  docs: path-lookup: i_op->follow_link replaced with i_op->get_link
  docs: path-lookup: Add macro name to symlink limit description
  docs: path-lookup: remove filename_mountpoint
  docs: path-lookup: update do_last() part
  docs: path-lookup: update path_mountpoint() part
  docs: path-lookup: update path_to_nameidata() part
  docs: path-lookup: update follow_managed() part
  docs: Makefile: Use CONFIG_SHELL not SHELL
  docs: Take a little noise out of the build process
  docs: x86: avoid using ReST :doc:`foo` markup
  docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup
  docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup
  docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup
  docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup
  ...
2021-06-28 16:53:05 -07:00
Mauro Carvalho Chehab
1a967a3122 docs: vm: zswap.rst: replace some characters
The conversion tools used during DocBook/LaTeX/html/Markdown->ReST
conversion and some cut-and-pasted text contain some characters that
aren't easily reachable on standard keyboards and/or could cause
troubles when parsed by the documentation build system.

Replace the occurences of the following characters:

	- U+00a0 (' '): NO-BREAK SPACE
	  as it can cause lines being truncated on PDF output

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9a93b72f99f8f3328269076ceff50248ac9c5af5.1623826294.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:22:33 -06:00
Kees Cook
8669dbab2a mm/slub: clarify verification reporting
Patch series "Actually fix freelist pointer vs redzoning", v4.

This fixes redzoning vs the freelist pointer (both for middle-position
and very small caches).  Both are "theoretical" fixes, in that I see no
evidence of such small-sized caches actually be used in the kernel, but
that's no reason to let the bugs continue to exist, especially since
people doing local development keep tripping over it.  :)

This patch (of 3):

Instead of repeating "Redzone" and "Poison", clarify which sides of
those zones got tripped.  Additionally fix column alignment in the
trailer.

Before:

  BUG test (Tainted: G    B            ): Redzone overwritten
  ...
  Redzone (____ptrval____): bb bb bb bb bb bb bb bb      ........
  Object (____ptrval____): f6 f4 a5 40 1d e8            ...@..
  Redzone (____ptrval____): 1a aa                        ..
  Padding (____ptrval____): 00 00 00 00 00 00 00 00      ........

After:

  BUG test (Tainted: G    B            ): Right Redzone overwritten
  ...
  Redzone  (____ptrval____): bb bb bb bb bb bb bb bb      ........
  Object   (____ptrval____): f6 f4 a5 40 1d e8            ...@..
  Redzone  (____ptrval____): 1a aa                        ..
  Padding  (____ptrval____): 00 00 00 00 00 00 00 00      ........

The earlier commits that slowly resulted in the "Before" reporting were:

  d86bd1bece ("mm/slub: support left redzone")
  ffc79d2880 ("slub: use print_hex_dump")
  2492268472 ("SLUB: change error reporting format to follow lockdep loosely")

Link: https://lkml.kernel.org/r/20210608183955.280836-1-keescook@chromium.org
Link: https://lkml.kernel.org/r/20210608183955.280836-2-keescook@chromium.org
Link: https://lore.kernel.org/lkml/cfdb11d7-fb8e-e578-c939-f7f5fb69a6bd@suse.cz/
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Marco Elver <elver@google.com>
Cc: "Lin, Zhenpeng" <zplin@psu.edu>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-16 09:24:42 -07:00
Yang Shi
4066c11948 mm: gup: remove FOLL_SPLIT
Since commit 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of
FOLL_SPLIT") and commit ba925fa350 ("s390/gmap: improve THP splitting")
FOLL_SPLIT has not been used anymore.  Remove the dead code.

Link: https://lkml.kernel.org/r/20210330203900.9222-1-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:37 -07:00
Georgi Djakov
866b485262 mm/page_owner: record the timestamp of all pages during free
Collect the time when each allocation is freed, to help with memory
analysis with kdump/ramdump.  Add the timestamp also in the page_owner
debugfs file and print it in dump_page().

Having another timestamp when we free the page helps for debugging page
migration issues.  For example both alloc and free timestamps being the
same can gave hints that there is an issue with migrating memory, as
opposed to a page just being dropped during migration.

Link: https://lkml.kernel.org/r/20210203175905.12267-1-georgi.djakov@linaro.org
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:36 -07:00
Anshuman Khandual
bb5c47ced4 mm/debug_vm_pgtable/basic: add validation for dirtiness after write protect
Patch series "mm/debug_vm_pgtable: Some minor updates", v3.

This series contains some cleanups and new test suggestions from Catalin
from an earlier discussion.

https://lore.kernel.org/linux-mm/20201123142237.GF17833@gaia/

This patch (of 2):

This adds validation tests for dirtiness after write protect conversion
for each page table level.  There are two new separate test types involved
here.

The first test ensures that a given page table entry does not become dirty
after pxx_wrprotect().  This is important for platforms like arm64 which
transfers and drops the hardware dirty bit (!PTE_RDONLY) to the software
dirty bit while making it an write protected one.  This test ensures that
no fresh page table entry could be created with hardware dirty bit set.
The second test ensures that a given page table entry always preserve the
dirty information across pxx_wrprotect().

This adds two previously missing PUD level basic tests and while here
fixes pxx_wrprotect() related typos in the documentation file.

Link: https://lkml.kernel.org/r/1611137241-26220-1-git-send-email-anshuman.khandual@arm.com
Link: https://lkml.kernel.org/r/1611137241-26220-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Steven Price <steven.price@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24 13:38:27 -08:00
Rolf Eike Beer
96c0f7c0b9 Documentation: fix typos in split page table lock description
Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Link: https://lore.kernel.org/r/2338863.uUFqZTUbry@devpool47
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-18 13:27:18 -07:00
Hugh Dickins
15b4473617 mm/lru: revise the comments of lru_lock
Since we changed the pgdat->lru_lock to lruvec->lru_lock, it's time to fix
the incorrect comments in code.  Also fixed some zone->lru_lock comment
error from ancient time.  etc.

I struggled to understand the comment above move_pages_to_lru() (surely
it never calls page_referenced()), and eventually realized that most of
it had got separated from shrink_active_list(): move that comment back.

Link: https://lkml.kernel.org/r/1604566549-62481-20-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Jann Horn <jannh@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Chen, Rong A" <rong.a.chen@intel.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 14:48:04 -08:00
Mike Rapoport
5e545df329 arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
ARM is the only architecture that defines CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
which in turn enables memmap_valid_within() function that is intended to
verify existence  of struct page associated with a pfn when there are holes
in the memory map.

However, the ARCH_HAS_HOLES_MEMORYMODEL also enables HAVE_ARCH_PFN_VALID
and arch-specific pfn_valid() implementation that also deals with the holes
in the memory map.

The only two users of memmap_valid_within() call this function after
a call to pfn_valid() so the memmap_valid_within() check becomes redundant.

Remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL and memmap_valid_within() and rely
entirely on ARM's implementation of pfn_valid() that is now enabled
unconditionally.

Link: https://lkml.kernel.org/r/20201101170454.9567-9-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Meelis Roos <mroos@linux.ee>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:42 -08:00
Liam Mark
9cc7e96aa8 mm/page_owner: record timestamp and pid
Collect the time for each allocation recorded in page owner so that
allocation "surges" can be measured.

Record the pid for each allocation recorded in page owner so that the
source of allocation "surges" can be better identified.

The above is very useful when doing memory analysis.  On a crash for
example, we can get this information from kdump (or ramdump) and parse it
to figure out memory allocation problems.

Please note that on x86_64 this increases the size of struct page_owner
from 16 bytes to 32.

Vlastimil: it's not a functionality intended for production, so unless
somebody says they need to enable page_owner for debugging and this
increase prevents them from fitting into available memory, let's not
complicate things with making this optional.

[lmark@codeaurora.org: v3]
  Link: https://lkml.kernel.org/r/20201210160357.27779-1-georgi.djakov@linaro.org

Link: https://lkml.kernel.org/r/20201209125153.10533-1-georgi.djakov@linaro.org
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:38 -08:00
Linus Torvalds
c80e42a496 A handful of late-arriving documentation fixes.
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Merge tag 'docs-5.10-2' of git://git.lwn.net/linux

Pull documentation fixes from Jonathan Corbet:
 "A handful of late-arriving documentation fixes"

* tag 'docs-5.10-2' of git://git.lwn.net/linux:
  docs: Add two missing entries in vm sysctl index
  docs/vm: trivial fixes to several spelling mistakes
  docs: submitting-patches: describe preserving review/test tags
  Documentation: Chinese translation of Documentation/arm64/hugetlbpage.rst
  Documentation: x86: fix a missing word in x86_64/mm.rst.
  docs: driver-api: remove a duplicated index entry
  docs: lkdtm: Modernize and improve details
  docs: deprecated.rst: Expand str*cpy() replacement notes
  docs/cpu-load: format the example code.
2020-10-23 17:13:53 -07:00
Colin Ian King
94ebdd28fc docs/vm: trivial fixes to several spelling mistakes
Fix several spelling mistakes in vm documentation.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20201022142653.254429-1-colin.king@canonical.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-22 16:11:04 -06:00
Mauro Carvalho Chehab
f910ce5266 mm/doc: fix a literal block markup
Literal blocks with :: markup should be indented, as otherwise
Sphinx complains:

	Documentation/vm/hmm.rst:363: WARNING: Literal block expected; none found.

Fixes: f7ebd9ed77 ("mm/doc: add usage description for migrate_vma_*()")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-16 07:28:20 +02:00
Mauro Carvalho Chehab
9303c9d5e9 docs: get rid of :c:type explicit declarations for structs
The :c:type:`foo` only works properly with structs before
Sphinx 3.x.

On Sphinx 3.x, structs should now be declared using the
.. c:struct, and referenced via :c:struct tag.

As we now have the automarkup.py macro, that automatically
convert:
	struct foo

into cross-references, let's get rid of that, solving
several warnings when building docs with Sphinx 3.x.

Reviewed-by: André Almeida <andrealmeid@collabora.com> # blk-mq.rst
Reviewed-by: Takashi Iwai <tiwai@suse.de> # sound
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:40 +02:00
Alexander Gordeev
25356cfad6 docs/vm: fix 'mm_count' vs 'mm_users' counter confusion
In the context of the anonymous address space lifespan description the
'mm_users' reference counter is confused with 'mm_count'.  I.e a "zombie"
mm gets released when "mm_count" becomes zero, not "mm_users".

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: https://lkml.kernel.org/r/1597040695-32633-1-git-send-email-agordeev@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:32 -07:00
Ralph Campbell
f7ebd9ed77 mm/doc: add usage description for migrate_vma_*()
The migrate_vma_setup(), migrate_vma_pages(), and migrate_vma_finalize()
API usage by device drivers is not well documented.
Add a description for how device drivers are expected to use it.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://lore.kernel.org/r/20200909212956.20104-1-rcampbell@nvidia.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-16 12:19:51 -06:00
Mauro Carvalho Chehab
4d05e3a0f5 docs: add some new files to their respective index.rst files
There were some new file additions for Kernel 5.7 and 5.8
that weren't added at the corresponding index file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9fd4d04f0d122ff38b5342a0098d99cc2f546652.1599660067.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-10 10:48:20 -06:00
Ralph Campbell
50aab9b142 mm/doc: editorial pass on page migration
Add Sphinx reference links to HMM and CPUSETS, and numerous small
editorial changes to make the page_migration.rst document more readable.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20200902225247.15213-1-rcampbell@nvidia.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-09 11:39:46 -06:00
Anshuman Khandual
1a5bae25e3 mm/vmstat: add events for THP migration without split
Add following new vmstat events which will help in validating THP
migration without split.  Statistics reported through these new VM events
will help in performance debugging.

1. THP_MIGRATION_SUCCESS
2. THP_MIGRATION_FAILURE
3. THP_MIGRATION_SPLIT

In addition, these new events also update normal page migration statistics
appropriately via PGMIGRATE_SUCCESS and PGMIGRATE_FAILURE.  While here,
this updates current trace event 'mm_migrate_pages' to accommodate now
available THP statistics.

[akpm@linux-foundation.org: s/hpage_nr_pages/thp_nr_pages/]
[ziy@nvidia.com: v2]
  Link: http://lkml.kernel.org/r/C5E3C65C-8253-4638-9D3C-71A61858BB8B@nvidia.com
[anshuman.khandual@arm.com: s/thp_nr_pages/hpage_nr_pages/]
  Link: http://lkml.kernel.org/r/1594287583-16568-1-git-send-email-anshuman.khandual@arm.com

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Link: http://lkml.kernel.org/r/1594080415-27924-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:57 -07:00
Mike Rapoport
c89ab04feb mm/sparse: cleanup the code surrounding memory_present()
After removal of CONFIG_HAVE_MEMBLOCK_NODE_MAP we have two equivalent
functions that call memory_present() for each region in memblock.memory:
sparse_memory_present_with_active_regions() and membocks_present().

Moreover, all architectures have a call to either of these functions
preceding the call to sparse_init() and in the most cases they are called
one after the other.

Mark the regions from memblock.memory as present during sparce_init() by
making sparse_init() call memblocks_present(), make memblocks_present()
and memory_present() functions static and remove redundant
sparse_memory_present_with_active_regions() function.

Also remove no longer required HAVE_MEMORY_PRESENT configuration option.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200712083130.22919-1-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:27 -07:00
Anshuman Khandual
56993b4e14 mm/sparsemem: enable vmem_altmap support in vmemmap_alloc_block_buf()
There are many instances where vmemap allocation is often switched between
regular memory and device memory just based on whether altmap is available
or not.  vmemmap_alloc_block_buf() is used in various platforms to
allocate vmemmap mappings.  Lets also enable it to handle altmap based
device memory allocation along with existing regular memory allocations.
This will help in avoiding the altmap based allocation switch in many
places.  To summarize there are two different methods to call
vmemmap_alloc_block_buf().

vmemmap_alloc_block_buf(size, node, NULL)   /* Allocate from system RAM */
vmemmap_alloc_block_buf(size, node, altmap) /* Allocate from altmap */

This converts altmap_alloc_block_buf() into a static function, drops it's
entry from the header and updates Documentation/vm/memory-model.rst.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jia He <justin.he@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yu Zhao <yuzhao@google.com>
Link: http://lkml.kernel.org/r/1594004178-8861-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:27 -07:00
Anshuman Khandual
b1d00007f2 Documentation/mm: add descriptions for arch page table helpers
This adds a specific description file for all arch page table helpers which
is in sync with the semantics being tested via CONFIG_DEBUG_VM_PGTABLE. All
future changes either to these descriptions here or the debug test should
always remain in sync.

[anshuman.khandual@arm.com: fold in Mike's patch for the rst document, fix typos in the rst document]
  Link: http://lkml.kernel.org/r/1594610587-4172-5-git-send-email-anshuman.khandual@arm.com

Suggested-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/1593996516-7186-5-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:23 -07:00
Vlastimil Babka
060807f841 mm, slub: make remaining slub_debug related attributes read-only
SLUB_DEBUG creates several files under /sys/kernel/slab/<cache>/ that can
be read to check if the respective debugging options are enabled for given
cache.  Some options, namely sanity_checks, trace, and failslab can be
also enabled and disabled at runtime by writing into the files.

The runtime toggling is racy.  Some options disable __CMPXCHG_DOUBLE when
enabled, which means that in case of concurrent allocations, some can
still use __CMPXCHG_DOUBLE and some not, leading to potential corruption.
The s->flags field is also not updated or checked atomically.  The
simplest solution is to remove the runtime toggling.  The extended
slub_debug boot parameter syntax introduced by earlier patch should allow
to fine-tune the debugging configuration during boot with same
granularity.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Jann Horn <jannh@google.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/20200610163135.17364-5-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
Vlastimil Babka
ad38b5b113 mm, slub: make some slub_debug related attributes read-only
SLUB_DEBUG creates several files under /sys/kernel/slab/<cache>/ that can
be read to check if the respective debugging options are enabled for given
cache.  The options can be also toggled at runtime by writing into the
files.  Some of those, namely red_zone, poison, and store_user can be
toggled only when no objects yet exist in the cache.

Vijayanand reports [1] that there is a problem with freelist randomization
if changing the debugging option's state results in different number of
objects per page, and the random sequence cache needs thus needs to be
recomputed.

However, another problem is that the check for "no objects yet exist in
the cache" is racy, as noted by Jann [2] and fixing that would add
overhead or otherwise complicate the allocation/freeing paths.  Thus it
would be much simpler just to remove the runtime toggling support.  The
documentation describes it's "In case you forgot to enable debugging on
the kernel command line", but the neccessity of having no objects limits
its usefulness anyway for many caches.

Vijayanand describes an use case [3] where debugging is enabled for all
but zram caches for memory overhead reasons, and using the runtime toggles
was the only way to achieve such configuration.  After the previous patch
it's now possible to do that directly from the kernel boot option, so we
can remove the dangerous runtime toggles by making the /sys attribute
files read-only.

While updating it, also improve the documentation of the debugging /sys files.

[1] https://lkml.kernel.org/r/1580379523-32272-1-git-send-email-vjitta@codeaurora.org
[2] https://lore.kernel.org/r/CAG48ez31PP--h6_FzVyfJ4H86QYczAFPdxtJHUEEan+7VJETAQ@mail.gmail.com
[3] https://lore.kernel.org/r/1383cd32-1ddc-4dac-b5f8-9c42282fa81c@codeaurora.org

Reported-by: Vijayanand Jitta <vjitta@codeaurora.org>
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/20200610163135.17364-3-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
Vlastimil Babka
e17f1dfba3 mm, slub: extend slub_debug syntax for multiple blocks
Patch series "slub_debug fixes and improvements".

The slub_debug kernel boot parameter can either apply a single set of
options to all caches or a list of caches.  There is a use case where
debugging is applied for all caches and then disabled at runtime for
specific caches, for performance and memory consumption reasons [1].  As
runtime changes are dangerous, extend the boot parameter syntax so that
multiple blocks of either global or slab-specific options can be
specified, with blocks delimited by ';'.  This will also support the use
case of [1] without runtime changes.

For details see the updated Documentation/vm/slub.rst

[1] https://lore.kernel.org/r/1383cd32-1ddc-4dac-b5f8-9c42282fa81c@codeaurora.org

[weiyongjun1@huawei.com: make parse_slub_debug_flags() static]
  Link: http://lkml.kernel.org/r/20200702150522.4940-1-weiyongjun1@huawei.com

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Jann Horn <jannh@google.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Link: http://lkml.kernel.org/r/20200610163135.17364-2-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
Randy Dunlap
18d97ed9b7 Documentation: vm/memory-model: eliminate duplicated word
Drop the doubled word "the".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Mike Rapoport <rppt@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20200707180414.10467-20-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-13 09:45:04 -06:00
Linus Torvalds
6d62c5b211 A handful of late-arriving docs fixes, along with a patch changing a lot of
HTTP links to HTTPS that had to be yanked and redone before the first
 pull.
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Merge tag 'docs-5.8-2' of git://git.lwn.net/linux

Pull more documentation updates from Jonathan Corbet:
 "A handful of late-arriving docs fixes, along with a patch changing a
  lot of HTTP links to HTTPS that had to be yanked and redone before the
  first pull"

* tag 'docs-5.8-2' of git://git.lwn.net/linux:
  docs/memory-barriers.txt/kokr: smp_mb__{before,after}_atomic(): update Documentation
  Documentation: devres: add missing entry for devm_platform_get_and_ioremap_resource()
  Replace HTTP links with HTTPS ones: documentation
  docs: it_IT: address invalid reference warnings
  doc: zh_CN: use doc reference to resolve undefined label warning
  docs: Update the location of the LF NDA program
  docs: dev-tools: coccinelle: underlines
2020-06-10 14:12:15 -07:00
Michel Lespinasse
c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
3e4e28c5a8 mmap locking API: convert mmap_sem API comments
Convert comments that reference old mmap_sem APIs to reference
corresponding new mmap locking APIs instead.

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-12-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Alexander A. Klimov
93431e0607 Replace HTTP links with HTTPS ones: documentation
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  For each line:
    If doesn't contain `\bxmlns\b`:
      For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
        If both the HTTP and HTTPS versions
        return 200 OK and serve the same content:
          Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200526060544.25127-1-grandmaster@al2klimov.de
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-08 09:30:19 -06:00
Changhee Han
5b94ce2fca tools/vm/page_owner_sort.c: filter out unneeded line
To see a sorted result from page_owner, there must be a tiresome
preprocessing step before running page_owner_sort.  This patch simply
filters out lines which start with "PFN" while reading the page owner
report.

Signed-off-by: Changhee Han <ch0.han@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: http://lkml.kernel.org/r/20200429052940.16968-1-ch0.han@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:49 -07:00
Mike Rapoport
237e506cd5 docs/vm: update memory-models documentation
To reflect the updates to free_area_init() family of functions.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Hoan Tran <hoan@os.amperecomputing.com>	[arm64]
Cc: Baoquan He <bhe@redhat.com>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200412194859.12663-22-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:44 -07:00
Linus Torvalds
cfa3b8068b hmm related patches for 5.8
This series adds a selftest for hmm_range_fault() and several of the
 DEVICE_PRIVATE migration related actions, and another simplification for
 hmm_range_fault()'s API.
 
 - Simplify hmm_range_fault() with a simpler return code, no
   HMM_PFN_SPECIAL, and no customizable output PFN format
 
 - Add a selftest for hmm_range_fault() and DEVICE_PRIVATE related
   functionality
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Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull hmm updates from Jason Gunthorpe:
 "This series adds a selftest for hmm_range_fault() and several of the
  DEVICE_PRIVATE migration related actions, and another simplification
  for hmm_range_fault()'s API.

   - Simplify hmm_range_fault() with a simpler return code, no
     HMM_PFN_SPECIAL, and no customizable output PFN format

   - Add a selftest for hmm_range_fault() and DEVICE_PRIVATE related
     functionality"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  MAINTAINERS: add HMM selftests
  mm/hmm/test: add selftests for HMM
  mm/hmm/test: add selftest driver for HMM
  mm/hmm: remove the customizable pfn format from hmm_range_fault
  mm/hmm: remove HMM_PFN_SPECIAL
  drm/amdgpu: remove dead code after hmm_range_fault()
  mm/hmm: make hmm_range_fault return 0 or -1
2020-06-02 14:05:27 -07:00
Linus Torvalds
94709049fb Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
 "A few little subsystems and a start of a lot of MM patches.

  Subsystems affected by this patch series: squashfs, ocfs2, parisc,
  vfs. With mm subsystems: slab-generic, slub, debug, pagecache, gup,
  swap, memcg, pagemap, memory-failure, vmalloc, kasan"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  kasan: move kasan_report() into report.c
  mm/mm_init.c: report kasan-tag information stored in page->flags
  ubsan: entirely disable alignment checks under UBSAN_TRAP
  kasan: fix clang compilation warning due to stack protector
  x86/mm: remove vmalloc faulting
  mm: remove vmalloc_sync_(un)mappings()
  x86/mm/32: implement arch_sync_kernel_mappings()
  x86/mm/64: implement arch_sync_kernel_mappings()
  mm/ioremap: track which page-table levels were modified
  mm/vmalloc: track which page-table levels were modified
  mm: add functions to track page directory modifications
  s390: use __vmalloc_node in stack_alloc
  powerpc: use __vmalloc_node in alloc_vm_stack
  arm64: use __vmalloc_node in arch_alloc_vmap_stack
  mm: remove vmalloc_user_node_flags
  mm: switch the test_vmalloc module to use __vmalloc_node
  mm: remove __vmalloc_node_flags_caller
  mm: remove both instances of __vmalloc_node_flags
  mm: remove the prot argument to __vmalloc_node
  mm: remove the pgprot argument to __vmalloc
  ...
2020-06-02 12:21:36 -07:00
Andrew Morton
a3df69278c Documentation/vm/slub.rst: s/Toggle/Enable/
"toggle" means to change a boolean thing's state.  This operation
doesn't do that - it sets it to "true".

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:06 -07:00
Sedat Dilek
9469b39072 zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
Recently, I switched over from swap-file to zramswap.

When reading the Documentation/vm/zswap.rst file I fell over this typo.

The parameter is called accept_threshold_percent not accept_threhsold_percent
in /sys/module/zswap/parameters/ directory.

Fixes: 45190f01dd ("mm/zswap.c: add allocation hysteresis if pool limit is hit")
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Link: https://lore.kernel.org/r/20200601005911.31222-1-sedat.dilek@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-01 09:33:23 -06:00
Kevin Hao
ea8fdf1a40 docs: vm: page_frags.rst: Fix the reference of stale function
The __netdev_alloc_frag() has been dropped by commit 7ba7aeabba ("net:
Don't disable interrupts in napi_alloc_frag()"). So replace it with
netdev_alloc_frag().

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Link: https://lore.kernel.org/r/20200508140924.18220-1-haokexin@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15 11:34:55 -06:00
Jason Gunthorpe
2733ea144d mm/hmm: remove the customizable pfn format from hmm_range_fault
Presumably the intent here was that hmm_range_fault() could put the data
into some HW specific format and thus avoid some work. However, nothing
actually does that, and it isn't clear how anything actually could do that
as hmm_range_fault() provides CPU addresses which must be DMA mapped.

Perhaps there is some special HW that does not need DMA mapping, but we
don't have any examples of this, and the theoretical performance win of
avoiding an extra scan over the pfns array doesn't seem worth the
complexity. Plus pfns needs to be scanned anyhow to sort out any
DEVICE_PRIVATE pages.

This version replaces the uint64_t with an usigned long containing a pfn
and fixed flags. On input flags is filled with the HMM_PFN_REQ_* values,
on successful output it is filled with HMM_PFN_* values, describing the
state of the pages.

amdgpu is simple to convert, it doesn't use snapshot and doesn't use
per-page flags.

nouveau uses only 16 hmm_pte entries at most (ie fits in a few cache
lines), and it sweeps over its pfns array a couple of times anyhow. It
also has a nasty call chain before it reaches the dma map and hardware
suggesting performance isn't important:

   nouveau_svm_fault():
     args.i.m.method = NVIF_VMM_V0_PFNMAP
     nouveau_range_fault()
      nvif_object_ioctl()
       client->driver->ioctl()
	  struct nvif_driver nvif_driver_nvkm:
	    .ioctl = nvkm_client_ioctl
	   nvkm_ioctl()
	    nvkm_ioctl_path()
	      nvkm_ioctl_v0[type].func(..)
	      nvkm_ioctl_mthd()
	       nvkm_object_mthd()
		  struct nvkm_object_func nvkm_uvmm:
		    .mthd = nvkm_uvmm_mthd
		   nvkm_uvmm_mthd()
		    nvkm_uvmm_mthd_pfnmap()
		     nvkm_vmm_pfn_map()
		      nvkm_vmm_ptes_get_map()
		       func == gp100_vmm_pgt_pfn
			struct nvkm_vmm_desc_func gp100_vmm_desc_spt:
			  .pfn = gp100_vmm_pgt_pfn
			 nvkm_vmm_iter()
			  REF_PTES == func == gp100_vmm_pgt_pfn()
			    dma_map_page()

Link: https://lore.kernel.org/r/5-v2-b4e84f444c7d+24f57-hmm_no_flags_jgg@mellanox.com
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-05-11 10:47:29 -03:00
Jason Gunthorpe
be957c886d mm/hmm: make hmm_range_fault return 0 or -1
hmm_vma_walk->last is supposed to be updated after every write to the
pfns, so that it can be returned by hmm_range_fault(). However, this is
not done consistently. Fortunately nothing checks the return code of
hmm_range_fault() for anything other than error.

More importantly last must be set before returning -EBUSY as it is used to
prevent reading an output pfn as an input flags when the loop restarts.

For clarity and simplicity make hmm_range_fault() return 0 or -ERRNO. Only
set last when returning -EBUSY.

Link: https://lore.kernel.org/r/2-v2-b4e84f444c7d+24f57-hmm_no_flags_jgg@mellanox.com
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-05-11 10:47:29 -03:00
Mauro Carvalho Chehab
9070492b10 docs: vm: index.rst: add an orphan doc to the building system
The new free_page_reporting.rst file is not listed at the index.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/146432ae6965a2bb62c929a6b62f9d4010986622.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:23 -06:00
Maciej S. Szmigiero
bb8b93b5b6 mm/zswap: allow setting default status, compressor and allocator in Kconfig
The compressed cache for swap pages (zswap) currently needs from 1 to 3
extra kernel command line parameters in order to make it work: it has to
be enabled by adding a "zswap.enabled=1" command line parameter and if one
wants a different compressor or pool allocator than the default lzo / zbud
combination then these choices also need to be specified on the kernel
command line in additional parameters.

Using a different compressor and allocator for zswap is actually pretty
common as guides often recommend using the lz4 / z3fold pair instead of
the default one.  In such case it is also necessary to remember to enable
the appropriate compression algorithm and pool allocator in the kernel
config manually.

Let's avoid the need for adding these kernel command line parameters and
automatically pull in the dependencies for the selected compressor
algorithm and pool allocator by adding an appropriate default switches to
Kconfig.

The default values for these options match what the code was using
previously as its defaults.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vitaly Wool <vitaly.wool@konsulko.com>
Link: http://lkml.kernel.org/r/20200202000112.456103-1-mail@maciej.szmigiero.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:41 -07:00
Alexander Duyck
1edca85e76 mm/page_reporting: add free page reporting documentation
Add documentation for free page reporting.  Currently the only consumer is
virtio-balloon, however it is possible that other drivers might make use
of this so it is best to add a bit of documetation explaining at a high
level how to use the API.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nitesh Narayan Lal <nitesh@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pagupta@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Yang Zhang <yang.zhang.wz@gmail.com>
Cc: wei qi <weiqi4@huawei.com>
Link: http://lkml.kernel.org/r/20200211224730.29318.43815.stgit@localhost.localdomain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:39 -07:00
Linus Torvalds
ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Jason Gunthorpe
6bfef2f919 mm/hmm: remove HMM_FAULT_SNAPSHOT
Now that flags are handled on a fine-grained per-page basis this global
flag is redundant and has a confusing overlap with the pfn_flags_mask and
default_flags.

Normalize the HMM_FAULT_SNAPSHOT behavior into one place. Callers needing
the SNAPSHOT behavior should set a pfn_flags_mask and default_flags that
always results in a cleared HMM_PFN_VALID. Then no pages will be faulted,
and HMM_FAULT_SNAPSHOT is not a special flow that overrides the masking
mechanism.

As this is the last flag, also remove the flags argument. If future flags
are needed they can be part of the struct hmm_range function arguments.

Link: https://lore.kernel.org/r/20200327200021.29372-5-jgg@ziepe.ca
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-27 20:19:24 -03:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Vitaly Wool
45190f01dd mm/zswap.c: add allocation hysteresis if pool limit is hit
zswap will always try to shrink pool when zswap is full.  If there is a
high pressure on zswap it will result in flipping pages in and out zswap
pool without any real benefit, and the overall system performance will
drop.  The previous discussion on this subject [1] ended up with a
suggestion to implement a sort of hysteresis to refuse taking pages into
zswap pool until it has sufficient space if the limit has been hit.
This is my take on this.

Hysteresis is controlled with a sysfs-configurable parameter (namely,
/sys/kernel/debug/zswap/accept_threhsold_percent).  It specifies the
threshold at which zswap would start accepting pages again after it
became full.  Setting this parameter to 100 disables the hysteresis and
sets the zswap behavior to pre-hysteresis state.

[1] https://lkml.org/lkml/2019/11/8/949

Link: http://lkml.kernel.org/r/20200108200118.15563-1-vitaly.wool@konsulko.com
Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31 10:30:39 -08:00
Jason Gunthorpe
5292e24a6a mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifier
The 'interval_sub' is placed on the 'notifier_subscriptions' interval
tree.

This eliminates the poor name 'mni' for this variable.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-14 11:54:47 -04:00
Jason Gunthorpe
a22dd50640 mm/hmm: remove hmm_mirror and related
The only two users of this are now converted to use mmu_interval_notifier,
delete all the code and update hmm.rst.

Link: https://lore.kernel.org/r/20191112202231.3856-14-jgg@ziepe.ca
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-11-23 19:56:45 -04:00
Mark Rutland
b4ed71f557 mm: treewide: clarify pgtable_page_{ctor,dtor}() naming
The naming of pgtable_page_{ctor,dtor}() seems to have confused a few
people, and until recently arm64 used these erroneously/pointlessly for
other levels of page table.

To make it incredibly clear that these only apply to the PTE level, and to
align with the naming of pgtable_pmd_page_{ctor,dtor}(), let's rename them
to pgtable_pte_page_{ctor,dtor}().

These changes were generated with the following shell script:

----
git grep -lw 'pgtable_page_.tor' | while read FILE; do
    sed -i '{s/pgtable_page_ctor/pgtable_pte_page_ctor/}' $FILE;
    sed -i '{s/pgtable_page_dtor/pgtable_pte_page_dtor/}' $FILE;
done
----

... with the documentation re-flowed to remain under 80 columns, and
whitespace fixed up in macros to keep backslashes aligned.

There should be no functional change as a result of this patch.

Link: http://lkml.kernel.org/r/20190722141133.3116-1-mark.rutland@arm.com
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-26 10:10:44 -07:00
Jason Gunthorpe
daa138a58c Merge branch 'odp_fixes' into hmm.git
From rdma.git

Jason Gunthorpe says:

====================
This is a collection of general cleanups for ODP to clarify some of the
flows around umem creation and use of the interval tree.
====================

The branch is based on v5.3-rc5 due to dependencies, and is being taken
into hmm.git due to dependencies in the next patches.

* odp_fixes:
  RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr
  RDMA/mlx5: Use ib_umem_start instead of umem.address
  RDMA/core: Make invalidate_range a device operation
  RDMA/odp: Use kvcalloc for the dma_list and page_list
  RDMA/odp: Check for overflow when computing the umem_odp end
  RDMA/odp: Provide ib_umem_odp_release() to undo the allocs
  RDMA/odp: Split creating a umem_odp from ib_umem_get
  RDMA/odp: Make the three ways to create a umem_odp clear
  RMDA/odp: Consolidate umem_odp initialization
  RDMA/odp: Make it clearer when a umem is an implicit ODP umem
  RDMA/odp: Iterate over the whole rbtree directly
  RDMA/odp: Use the common interval tree library instead of generic
  RDMA/mlx5: Fix MR npages calculation for IB_ACCESS_HUGETLB

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-21 20:58:18 -03:00
Christoph Hellwig
a7d1f22bb7 mm: turn migrate_vma upside down
There isn't any good reason to pass callbacks to migrate_vma.  Instead
we can just export the three steps done by this function to drivers and
let them sequence the operation without callbacks.  This removes a lot
of boilerplate code as-is, and will allow the drivers to drastically
improve code flow and error handling further on.

Link: https://lore.kernel.org/r/20190814075928.23766-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-20 09:35:02 -03:00
Christoph Hellwig
fac555ac93 mm/hmm: remove superfluous arguments from hmm_range_register
The start, end and page_shift values are all saved in the range structure,
so we might as well use that for argument passing.

Link: https://lore.kernel.org/r/20190806160554.14046-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-07 14:58:05 -03:00
Linus Torvalds
515f12b9ee HMM patches for 5.3-rc
Fix the locking around nouveau's use of the hmm_range_* APIs. It works
 correctly in the success case, but many of the the edge cases have missing
 unlocks or double unlocks.
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Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull HMM fixes from Jason Gunthorpe:
 "Fix the locking around nouveau's use of the hmm_range_* APIs. It works
  correctly in the success case, but many of the the edge cases have
  missing unlocks or double unlocks.

  The diffstat is a bit big as Christoph did a comprehensive job to move
  the obsolete API from the core header and into the driver before
  fixing its flow, but the risk of regression from this code motion is
  low"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  nouveau: unlock mmap_sem on all errors from nouveau_range_fault
  nouveau: remove the block parameter to nouveau_range_fault
  mm/hmm: move hmm_vma_range_done and hmm_vma_fault to nouveau
  mm/hmm: always return EBUSY for invalid ranges in hmm_range_{fault,snapshot}
2019-07-30 12:54:44 -07:00
Christoph Hellwig
d45d464b11 mm/hmm: merge hmm_range_snapshot into hmm_range_fault
Add a HMM_FAULT_SNAPSHOT flag so that hmm_range_snapshot can be merged
into the almost identical hmm_range_fault function.

Link: https://lore.kernel.org/r/20190726005650.2566-5-rcampbell@nvidia.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-26 11:10:53 -03:00
Christoph Hellwig
2bcbeaefde mm/hmm: always return EBUSY for invalid ranges in hmm_range_{fault,snapshot}
We should not have two different error codes for the same
condition. EAGAIN must be reserved for the FAULT_FLAG_ALLOW_RETRY retry
case and signals to the caller that the mmap_sem has been unlocked.

Use EBUSY for the !valid case so that callers can get the locking right.

Link: https://lore.kernel.org/r/20190724065258.16603-2-hch@lst.de
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
[jgg: elaborated commit message]
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-25 16:14:39 -03:00
Jonathan Corbet
48ffc3d12b Merge branch 'pdf_fixes_v1' of https://git.linuxtv.org/mchehab/experimental into mauro
Bring in a set of post-thrashup fixes from Mauro.
2019-07-22 13:51:20 -06:00
Dan Williams
a0653406a3 mm: document ZONE_DEVICE memory-model implications
Explain the general mechanisms of 'ZONE_DEVICE' pages and list the users
of 'devm_memremap_pages()'.

[dan.j.williams@intel.com: update ZONE_DEVICE memory model documentation]
  Link: http://lkml.kernel.org/r/156109575458.1409767.1885676287099277666.stgit@dwillia2-desk3.amr.corp.intel.com
Link: http://lkml.kernel.org/r/156092354985.979959.15763234410543451710.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>	[ppc64]
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18 17:08:07 -07:00
Mauro Carvalho Chehab
9fc3a18a94 docs: remove extra conf.py files
Now that the latex_documents are handled automatically, we can
remove those extra conf.py files.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-17 06:57:52 -03:00
Mauro Carvalho Chehab
da82c92f11 docs: cgroup-v1: add it to the admin-guide book
Those files belong to the admin guide, so add them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 11:03:02 -03:00
Mauro Carvalho Chehab
5704324702 docs: admin-guide: move sysctl directory to it
The stuff under sysctl describes /sys interface from userspace
point of view. So, add it to the admin-guide and remove the
:orphan: from its index file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 11:03:01 -03:00
Mauro Carvalho Chehab
53b9537509 docs: sysctl: convert to ReST
Rename the /proc/sys/ documentation files to ReST, using the
README file as a template for an index.rst, adding the other
files there via TOC markup.

Despite being written on different times with different
styles, try to make them somewhat coherent with a similar
look and feel, ensuring that they'll look nice as both
raw text file and as via the html output produced by the
Sphinx build system.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 09:20:26 -03:00
Linus Torvalds
fec88ab0af HMM patches for 5.3
Improvements and bug fixes for the hmm interface in the kernel:
 
 - Improve clarity, locking and APIs related to the 'hmm mirror' feature
   merged last cycle. In linux-next we now see AMDGPU and nouveau to be
   using this API.
 
 - Remove old or transitional hmm APIs. These are hold overs from the past
   with no users, or APIs that existed only to manage cross tree conflicts.
   There are still a few more of these cleanups that didn't make the merge
   window cut off.
 
 - Improve some core mm APIs:
   * export alloc_pages_vma() for driver use
   * refactor into devm_request_free_mem_region() to manage
     DEVICE_PRIVATE resource reservations
   * refactor duplicative driver code into the core dev_pagemap
     struct
 
 - Remove hmm wrappers of improved core mm APIs, instead have drivers use
   the simplified API directly
 
 - Remove DEVICE_PUBLIC
 
 - Simplify the kconfig flow for the hmm users and core code
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Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull HMM updates from Jason Gunthorpe:
 "Improvements and bug fixes for the hmm interface in the kernel:

   - Improve clarity, locking and APIs related to the 'hmm mirror'
     feature merged last cycle. In linux-next we now see AMDGPU and
     nouveau to be using this API.

   - Remove old or transitional hmm APIs. These are hold overs from the
     past with no users, or APIs that existed only to manage cross tree
     conflicts. There are still a few more of these cleanups that didn't
     make the merge window cut off.

   - Improve some core mm APIs:
       - export alloc_pages_vma() for driver use
       - refactor into devm_request_free_mem_region() to manage
         DEVICE_PRIVATE resource reservations
       - refactor duplicative driver code into the core dev_pagemap
         struct

   - Remove hmm wrappers of improved core mm APIs, instead have drivers
     use the simplified API directly

   - Remove DEVICE_PUBLIC

   - Simplify the kconfig flow for the hmm users and core code"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (42 commits)
  mm: don't select MIGRATE_VMA_HELPER from HMM_MIRROR
  mm: remove the HMM config option
  mm: sort out the DEVICE_PRIVATE Kconfig mess
  mm: simplify ZONE_DEVICE page private data
  mm: remove hmm_devmem_add
  mm: remove hmm_vma_alloc_locked_page
  nouveau: use devm_memremap_pages directly
  nouveau: use alloc_page_vma directly
  PCI/P2PDMA: use the dev_pagemap internal refcount
  device-dax: use the dev_pagemap internal refcount
  memremap: provide an optional internal refcount in struct dev_pagemap
  memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag
  memremap: remove the data field in struct dev_pagemap
  memremap: add a migrate_to_ram method to struct dev_pagemap_ops
  memremap: lift the devmap_enable manipulation into devm_memremap_pages
  memremap: pass a struct dev_pagemap to ->kill and ->cleanup
  memremap: move dev_pagemap callbacks into a separate structure
  memremap: validate the pagemap type passed to devm_memremap_pages
  mm: factor out a devm_request_free_mem_region helper
  mm: export alloc_pages_vma
  ...
2019-07-14 19:42:11 -07:00
Linus Torvalds
e9a83bd232 It's been a relatively busy cycle for docs:
- A fair pile of RST conversions, many from Mauro.  These create more
    than the usual number of simple but annoying merge conflicts with other
    trees, unfortunately.  He has a lot more of these waiting on the wings
    that, I think, will go to you directly later on.
 
  - A new document on how to use merges and rebases in kernel repos, and one
    on Spectre vulnerabilities.
 
  - Various improvements to the build system, including automatic markup of
    function() references because some people, for reasons I will never
    understand, were of the opinion that :c:func:``function()`` is
    unattractive and not fun to type.
 
  - We now recommend using sphinx 1.7, but still support back to 1.4.
 
  - Lots of smaller improvements, warning fixes, typo fixes, etc.
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Merge tag 'docs-5.3' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle for docs:

   - A fair pile of RST conversions, many from Mauro. These create more
     than the usual number of simple but annoying merge conflicts with
     other trees, unfortunately. He has a lot more of these waiting on
     the wings that, I think, will go to you directly later on.

   - A new document on how to use merges and rebases in kernel repos,
     and one on Spectre vulnerabilities.

   - Various improvements to the build system, including automatic
     markup of function() references because some people, for reasons I
     will never understand, were of the opinion that
     :c:func:``function()`` is unattractive and not fun to type.

   - We now recommend using sphinx 1.7, but still support back to 1.4.

   - Lots of smaller improvements, warning fixes, typo fixes, etc"

* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
  docs: automarkup.py: ignore exceptions when seeking for xrefs
  docs: Move binderfs to admin-guide
  Disable Sphinx SmartyPants in HTML output
  doc: RCU callback locks need only _bh, not necessarily _irq
  docs: format kernel-parameters -- as code
  Doc : doc-guide : Fix a typo
  platform: x86: get rid of a non-existent document
  Add the RCU docs to the core-api manual
  Documentation: RCU: Add TOC tree hooks
  Documentation: RCU: Rename txt files to rst
  Documentation: RCU: Convert RCU UP systems to reST
  Documentation: RCU: Convert RCU linked list to reST
  Documentation: RCU: Convert RCU basic concepts to reST
  docs: filesystems: Remove uneeded .rst extension on toctables
  scripts/sphinx-pre-install: fix out-of-tree build
  docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
  Documentation: PGP: update for newer HW devices
  Documentation: Add section about CPU vulnerabilities for Spectre
  Documentation: platform: Delete x86-laptop-drivers.txt
  docs: Note that :c:func: should no longer be used
  ...
2019-07-09 12:34:26 -07:00
Linus Torvalds
92c1d65221 Merge branch 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "Documentation updates and the addition of cgroup_parse_float() which
  will be used by new controllers including blk-iocost"

* 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs: cgroup-v1: convert docs to ReST and rename to *.rst
  cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS
  cgroup: add cgroup_parse_float()
2019-07-08 21:35:12 -07:00
Jason Gunthorpe
cc5dfd59e3 Merge branch 'hmm-devmem-cleanup.4' into rdma.git hmm
Christoph Hellwig says:

====================
Below is a series that cleans up the dev_pagemap interface so that it is
more easily usable, which removes the need to wrap it in hmm and thus
allowing to kill a lot of code

Changes since v3:
 - pull in "mm/swap: Fix release_pages() when releasing devmap pages" and
   rebase the other patches on top of that
 - fold the hmm_devmem_add_resource into the DEVICE_PUBLIC memory removal
   patch
 - remove _vm_normal_page as it isn't needed without DEVICE_PUBLIC memory
 - pick up various ACKs

Changes since v2:
 - fix nvdimm kunit build
 - add a new memory type for device dax
 - fix a few issues in intermediate patches that didn't show up in the end
   result
 - incorporate feedback from Michal Hocko, including killing of
   the DEVICE_PUBLIC memory type entirely

Changes since v1:
 - rebase
 - also switch p2pdma to the internal refcount
 - add type checking for pgmap->type
 - rename the migrate method to migrate_to_ram
 - cleanup the altmap_valid flag
 - various tidbits from the reviews
====================

Conflicts resolved by:
 - Keeping Ira's version of the code in swap.c
 - Using the delete for the section in hmm.rst
 - Using the delete for the devmap code in hmm.c and .h

* branch 'hmm-devmem-cleanup.4': (24 commits)
  mm: don't select MIGRATE_VMA_HELPER from HMM_MIRROR
  mm: remove the HMM config option
  mm: sort out the DEVICE_PRIVATE Kconfig mess
  mm: simplify ZONE_DEVICE page private data
  mm: remove hmm_devmem_add
  mm: remove hmm_vma_alloc_locked_page
  nouveau: use devm_memremap_pages directly
  nouveau: use alloc_page_vma directly
  PCI/P2PDMA: use the dev_pagemap internal refcount
  device-dax: use the dev_pagemap internal refcount
  memremap: provide an optional internal refcount in struct dev_pagemap
  memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag
  memremap: remove the data field in struct dev_pagemap
  memremap: add a migrate_to_ram method to struct dev_pagemap_ops
  memremap: lift the devmap_enable manipulation into devm_memremap_pages
  memremap: pass a struct dev_pagemap to ->kill and ->cleanup
  memremap: move dev_pagemap callbacks into a separate structure
  memremap: validate the pagemap type passed to devm_memremap_pages
  mm: factor out a devm_request_free_mem_region helper
  mm: export alloc_pages_vma
  ...

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-02 15:10:45 -03:00
Christoph Hellwig
eee3ae41b1 mm: remove hmm_devmem_add
There isn't really much value add in the hmm_devmem_add wrapper and
more, as using devm_memremap_pages directly now is just as simple.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-02 14:32:45 -03:00
Valentin Schneider
22aac85739 docs/vm: hwpoison.rst: Fix quote formatting
The asterisks prepended to the quoted text currently get translated to
bullet points, which gets increasingly confusing the smaller your
screen is (when viewing the sphinx output, that is).

Convert the whole quote to a literal block.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-20 14:11:32 -06:00
Mauro Carvalho Chehab
d6a3b24762 docs: scheduler: convert docs to ReST and rename to *.rst
In order to prepare to add them to the Kernel API book,
convert the files to ReST format.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14 14:32:18 -06:00
Mauro Carvalho Chehab
99c8b231ae docs: cgroup-v1: convert docs to ReST and rename to *.rst
Convert the cgroup-v1 files to ReST format, in order to
allow a later addition to the admin-guide.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-06-14 13:29:54 -07:00
Ralph Campbell
2076e5c045 mm/hmm: update HMM documentation
Update the HMM documentation to reflect the latest API and make a few
minor wording changes.

Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-06-06 16:31:40 -03:00
Randy Dunlap
91173c6e18 mm: fix Documentation/vm/hmm.rst Sphinx warnings
Fix Sphinx warnings in Documentation/vm/hmm.rst by using "::" notation and
inserting a blank line.  Also add a missing ';'.

  Documentation/vm/hmm.rst:292: WARNING: Unexpected indentation.
  Documentation/vm/hmm.rst:300: WARNING: Unexpected indentation.

Link: http://lkml.kernel.org/r/c5995359-7c82-4e47-c7be-b58a4dda0953@infradead.org
Fixes: 023a019a9b ("mm/hmm: add default fault flags to avoid the need to pre-fill pfns arrays")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:31 -07:00
Jérôme Glisse
023a019a9b mm/hmm: add default fault flags to avoid the need to pre-fill pfns arrays
The HMM mirror API can be use in two fashions.  The first one where the
HMM user coalesce multiple page faults into one request and set flags per
pfns for of those faults.  The second one where the HMM user want to
pre-fault a range with specific flags.  For the latter one it is a waste
to have the user pre-fill the pfn arrays with a default flags value.

This patch adds a default flags value allowing user to set them for a
range without having to pre-fill the pfn array.

Link: http://lkml.kernel.org/r/20190403193318.16478-8-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:48 -07:00
Jérôme Glisse
a3e0d41c2b mm/hmm: improve driver API to work and wait over a range
A common use case for HMM mirror is user trying to mirror a range and
before they could program the hardware it get invalidated by some core mm
event.  Instead of having user re-try right away to mirror the range
provide a completion mechanism for them to wait for any active
invalidation affecting the range.

This also changes how hmm_range_snapshot() and hmm_range_fault() works by
not relying on vma so that we can drop the mmap_sem when waiting and
lookup the vma again on retry.

Link: http://lkml.kernel.org/r/20190403193318.16478-7-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:48 -07:00
Jérôme Glisse
73231612dc mm/hmm: improve and rename hmm_vma_fault() to hmm_range_fault()
Minor optimization around hmm_pte_need_fault().  Rename for consistency
between code, comments and documentation.  Also improves the comments on
all the possible returns values.  Improve the function by returning the
number of populated entries in pfns array.

Link: http://lkml.kernel.org/r/20190403193318.16478-6-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:48 -07:00
Jérôme Glisse
25f23a0c71 mm/hmm: improve and rename hmm_vma_get_pfns() to hmm_range_snapshot()
Rename for consistency between code, comments and documentation.  Also
improves the comments on all the possible returns values.  Improve the
function by returning the number of populated entries in pfns array.

Link: http://lkml.kernel.org/r/20190403193318.16478-5-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:48 -07:00
Ralph Campbell
41f0a9542a docs/vm: Minor editorial changes in the THP and hugetlbfs
Some minor wording changes and typo corrections.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-04-30 06:34:40 -06:00
Mike Rapoport
7d10bdbd6d docs/vm: add documentation of memory models
Describe what {FLAT,DISCONTIG,SPARSE}MEM are and how they manage to
maintain pfn <-> struct page correspondence.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-04-30 06:30:01 -06:00
Yang Shi
a496696ab5 doc: mm: migration doesn't use FOLL_SPLIT anymore
When demonstrating FOLL_SPLIT in transhuge document, migration is used
as an example.  But, since commit 94723aafb9 ("mm: unclutter THP
migration"), the way of THP migration is totally changed.  FOLL_SPLIT is
not used by migration anymore due to the change.

Remove the obsolete example to avoid confusion.

Cc: Michal Hocko <mhocko@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-04-19 12:48:06 -06:00
Tobin C. Harding
66e9c46c5c docs: Use reference to link to rst file
Current document includes the path to an RST doc file.  Since this is an
RST file we can make this a link.  Keeps the path as the link title
since that what the original author wrote.

Use reference to link to rst file.

Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-04-09 15:21:17 -06:00
Tobin C. Harding
cd7198fc95 docs: Use underscore not hyphen in label
sphinx emits warning

       WARNING: undefined label: memory-allocation ...

This seems to be caused by the use of a hyphen in the label name instead
of an underscore.  Using an underscore for the label name and the
reference clears the warning.

Use underscore not hyphen in label and reference.

Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-02-01 16:04:01 -07:00
Tobin C. Harding
11ede50059 docs: Add missing colon
sphinx emits warning

       WARNING: Inline emphasis start-string without end-string.

This is caused by a missing colon.

Add missing colon, clearing shpinx build warning.

Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-02-01 16:03:45 -07:00
Tobin C. Harding
358b6ba9be docs: Fix SLUB docs typo
There is a minor typo in SLUB documentation.

Fix typo.

Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-02-01 16:03:25 -07:00
Linus Torvalds
3868772b99 A fairly normal cycle for documentation stuff. We have a new
document on perf security, more Italian translations, more
 improvements to the memory-management docs, improvements to the
 pathname lookup documentation, and the usual array of smaller
 fixes.
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Merge tag 'docs-5.0' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "A fairly normal cycle for documentation stuff. We have a new document
  on perf security, more Italian translations, more improvements to the
  memory-management docs, improvements to the pathname lookup
  documentation, and the usual array of smaller fixes.

  As is often the case, there are a few reaches outside of
  Documentation/ to adjust kerneldoc comments"

* tag 'docs-5.0' of git://git.lwn.net/linux: (38 commits)
  docs: improve pathname-lookup document structure
  configfs: fix wrong name of struct in documentation
  docs/mm-api: link slab_common.c to "The Slab Cache" section
  slab: make kmem_cache_create{_usercopy} description proper kernel-doc
  doc:process: add links where missing
  docs/core-api: make mm-api.rst more structured
  x86, boot: documentation whitespace fixup
  Documentation: devres: note checking needs when converting
  doc🇮🇹 add some process/* translations
  doc🇮🇹 fixes in process/1.Intro
  Documentation: convert path-lookup from markdown to resturctured text
  Documentation/admin-guide: update admin-guide index.rst
  Documentation/admin-guide: introduce perf-security.rst file
  scripts/kernel-doc: Fix struct and struct field attribute processing
  Documentation: dev-tools: Fix typos in index.rst
  Correct gen_init_cpio tool's documentation
  Document /proc/pid PID reuse behavior
  Documentation: update path-lookup.md for parallel lookups
  Documentation: Use "while" instead of "whilst"
  dmaengine: Add mailing list address to the documentation
  ...
2018-12-29 11:21:49 -08:00
Matthew Wilcox
acf0f57a2c Link the memory allocation guide from the MM docs
I just went looking for the memory allocation guide in the MM docs instead
of in the core API.  For the benefit of the next person who makes that
mistake, link to it from the MM docs.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20 09:17:40 -07:00
Jani Nikula
2ac5e38ea4 Merge drm/drm-next into drm-intel-next-queued
Pull in v4.20-rc3 via drm-next.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2018-11-20 13:14:08 +02:00
Kuo-Hsin Yang
64e3d12f76 mm, drm/i915: mark pinned shmemfs pages as unevictable
The i915 driver uses shmemfs to allocate backing storage for gem
objects. These shmemfs pages can be pinned (increased ref count) by
shmem_read_mapping_page_gfp(). When a lot of pages are pinned, vmscan
wastes a lot of time scanning these pinned pages. In some extreme case,
all pages in the inactive anon lru are pinned, and only the inactive
anon lru is scanned due to inactive_ratio, the system cannot swap and
invokes the oom-killer. Mark these pinned pages as unevictable to speed
up vmscan.

Export pagevec API check_move_unevictable_pages().

This patch was inspired by Chris Wilson's change [1].

[1]: https://patchwork.kernel.org/patch/9768741/

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Kuo-Hsin Yang <vovoy@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com> # mm part
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20181106132324.17390-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2018-11-07 15:28:32 +00:00
Aaron Tomlin
c5fd3ca06b slub: extend slub debug to handle multiple slabs
Extend the slub_debug syntax to "slub_debug=<flags>[,<slub>]*", where
<slub> may contain an asterisk at the end.  For example, the following
would poison all kmalloc slabs:

	slub_debug=P,kmalloc*

and the following would apply the default flags to all kmalloc and all
block IO slabs:

	slub_debug=,bio*,kmalloc*

Please note that a similar patch was posted by Iliyan Malchev some time
ago but was never merged:

	https://marc.info/?l=linux-mm&m=131283905330474&w=2

Link: http://lkml.kernel.org/r/20180928111139.27962-1-atomlin@redhat.com
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Iliyan Malchev <malchev@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Henrik Austad
a7ddcea58a Drop all 00-INDEX files from Documentation/
This is a respin with a wider audience (all that get_maintainer returned)
and I know this spams a *lot* of people. Not sure what would be the correct
way, so my apologies for ruining your inbox.

The 00-INDEX files are supposed to give a summary of all files present
in a directory, but these files are horribly out of date and their
usefulness is brought into question. Often a simple "ls" would reveal
the same information as the filenames are generally quite descriptive as
a short introduction to what the file covers (it should not surprise
anyone what Documentation/sched/sched-design-CFS.txt covers)

A few years back it was mentioned that these files were no longer really
needed, and they have since then grown further out of date, so perhaps
it is time to just throw them out.

A short status yields the following _outdated_ 00-INDEX files, first
counter is files listed in 00-INDEX but missing in the directory, last
is files present but not listed in 00-INDEX.

List of outdated 00-INDEX:
Documentation: (4/10)
Documentation/sysctl: (0/1)
Documentation/timers: (1/0)
Documentation/blockdev: (3/1)
Documentation/w1/slaves: (0/1)
Documentation/locking: (0/1)
Documentation/devicetree: (0/5)
Documentation/power: (1/1)
Documentation/powerpc: (0/5)
Documentation/arm: (1/0)
Documentation/x86: (0/9)
Documentation/x86/x86_64: (1/1)
Documentation/scsi: (4/4)
Documentation/filesystems: (2/9)
Documentation/filesystems/nfs: (0/2)
Documentation/cgroup-v1: (0/2)
Documentation/kbuild: (0/4)
Documentation/spi: (1/0)
Documentation/virtual/kvm: (1/0)
Documentation/scheduler: (0/2)
Documentation/fb: (0/1)
Documentation/block: (0/1)
Documentation/networking: (6/37)
Documentation/vm: (1/3)

Then there are 364 subdirectories in Documentation/ with several files that
are missing 00-INDEX alltogether (and another 120 with a single file and no
00-INDEX).

I don't really have an opinion to whether or not we /should/ have 00-INDEX,
but the above 00-INDEX should either be removed or be kept up to date. If
we should keep the files, I can try to keep them updated, but I rather not
if we just want to delete them anyway.

As a starting point, remove all index-files and references to 00-INDEX and
see where the discussion is going.

Signed-off-by: Henrik Austad <henrik@austad.us>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Just-do-it-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: [Almost everybody else]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-09-09 15:08:58 -06:00
Baoquan He
74f0fc936c docs/vm/hmm.rst: Add missed space
This space missing caused the colour scheme in vim editor messy
after that line. Add it to fix.

Signed-off-by: Baoquan He <bhe@redhat.com>
[ jc: fixed alignment after the changed line ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-08-31 16:22:12 -06:00
Mike Rapoport
ba22931235 docs/vm: move ksm and transhuge from "user" to "internals" section.
After the userspace interface description for KSM and THP was split to
Documentation/admin-guide/mm, the remaining parts belong to the section
describing MM internals.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-05-29 06:45:55 -06:00